去中心化金融(DeFi)作为区块链生态当红项目形态，其安全尤为重要。从去年至今，发生了几十起安全事件
BlockSec作为长期关注DeFi安全的研究团队(https://blocksecteam
_toWETH函数：
function_toWETH(addresstoken)internalreturns(uint256){//对于SUSHI，直接Sushimaker全部SUSHI转给Barif(token==sushi){uintamount=IERC20(token)
//对于WETH，直接将全部WETH转给WETH/SUSHI交易对，swap出相应的SUSHIif(token==weth){uintamount=IERC20(token)
//获取token/WETH的交易对地址IUniswapV2Pairpair=IUniswapV2Pair(factory
//计算可以换出的WETH数量：amount0out，amount1Out//获得交易对中两种资产的数量(uintreserve0,uintreserve1,)=pair
看出什么亮点了吗？
SushiMaker里的转账逻辑都是：transfer(balanceOf(this))
我们可以分两个阶段来看convert的调用过程：第一个阶段：在convert函数中SushiMaker拥有的是SLP，它通过burnbalanceOf(this)实现将全部SLP换成两个底层代币第二个阶段：SushiMaker获得了burn来的底层代币，再拿burn得到的token去不同的交易池换wETH
你发现哪里有问题了吗？我们来看第二阶段的代码_toWETH：注意兑换的逻辑为：
uintamount=IERC20(token)
,"profit":"0
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俄勒冈州金融监管部将从BlockFi获得近100万美元和解金:7月1日消息，作为加密货币金融机构 BlockFi 与美国多州和解协议的一部分，俄勒冈州金融监管部将从 BlockFi 获得近 100 万美元赔偿。此前，俄勒冈州金融监管部对 BlockFi 违反俄勒冈州证券法提起了法律诉讼，声称 BlockFi 在未经适当注册的情况下在俄勒冈州提供和出售证券此外，BlockFi 向公众提供利息账户（BIA），通过利息账户，投资者可以将比特币和以太坊等加密货币存入，然后将加密资产借给 BlockFi，以换取该公司承诺提供可变的每月利息支付，BlockFi 承诺的月利率为 6.2%，根据投资的类型和规模，每个月的复合利率最高可达 9.5%。
作为与证券监管机构和解的一部分，BlockFi 同意支付总计约 1 亿美元的和解金，其中一半将支付给美国证券交易委员会，另一半支付给各州证券监管机构。BlockFi 将停止向俄勒冈州的新投资者提供利息账户或出售任何未注册、合格或豁免的证券，并向俄勒冈州金融监管部支付 943,396 美元。（KTVZ）[2022/7/1 1:44:22]
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动态 | 泰国Block chainstore旗下ECOC主网将于10月28日上线:据泰国Block chainstore官方消息，其旗下ECOC主网将于2019年10月28日正式上线。据介绍，ECOC采用POS共识，侧重区块链共识底层技术安全及TPS交易速度（560/M），同步可扩展智能合约跨链功能。[2019/10/21]
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,{"SEEN/WETH":{"0xc6b39015ab0a32762fb23108e9705cb30d171374c7f9d4b9cf30e640f43d4884":"PreAttack","0x3c14c48007147f78ae3c3ac5d56f74413ebc468c6e09f7eb1098c19b9b546185":"Convert","0x8681b43b4814bb54f49650b19d42133c933bcdbc65dfcd36a6cadf7ef916391c":"Swap"},"profit":"1
动态 | BM 透露 Block.one 也会开发 Android 钱包:据 IMEOS 报道，继此前 BM 提到 Block.one 会开发 EOS 的 IOS 钱包后，在回答社区成员提问时， BM 刚刚透露Android EOS 钱包也会开发。[2018/8/10]
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,{"SNX/WETH":{"0x7eea5790e31176d45b944c0f2624c30a755650b1a353e052191e36d23db2abbc":"PreAttack","0x1518424118b519af43657d5de42311f5b5174aab941ff1b7bfe14b0ef5d0874a":"Convert","0x04cd83c93cf8f37fbafb7d05d5f34cb23bcef8871b2744efad517e6aab38395c":"Swap"},"profit":"0
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蚂蚁技术实验室发布全球首款区块链喷漆Block 7:蚂蚁技术实验室发布全球首款区块链喷漆Block 7，据悉将这款漆喷在车上，就能将汽车变成区块链上的节点。遇上车辆事故，汽车上的各种传感器会自动将本车车体形变、行人间距、视频记录做好数据安全转换后上链，同时请求附近上链的汽车、智能路灯、摄像头等交通设施联合作证，通过多方交叉验证，迅速还原真实现场。[2018/4/2]
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,{"zLOT/WETH":{"0x0bb5d792a1d1ea598e45997d5dedb4fcf6acafab47afdb45892417cd128cf37f":"PreAttack","0x2550eb33adbe7cfb68cce685363ad2cab90860e5e8a8ed87de1f0a6321e24cf8":"Convert","0x514bd13f68c8afc1f86ea3e74ca5f51724c2736fa327144b7b6aaf7228bd9124":"Swap"},"profit":"0
Blockstream新推出闪电网络应用程序解决闪电支付的小费问题:Blockstream发布公告宣布推出新应用Nanotip LApp。Nanipip LApp通过创建一个简单的Web服务器，即时编写闪电支付请求，解决了闪电支付小费支付的请求问题。它为每个内容提供商提供了他们自己的的支付机器人（tip-bot），但是这样做的方式可以让这些创作者完全控制消费致富，同时赋予他们比传统比特币支付小费更强的隐私。这是Blockstream推出的第三款闪电网络应用程序。[2018/3/27]
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,{"DAI/WETH":{"0x6964f68672edb916ae170254ee48c537cbb64ca0584651d21fd575550559354f":"PreAttack","0x61856228835bfd97dc6b9d7674aaabb577b74fa7d7ff7b7f45454a8d521ff533":"Convert","0x053ebfe8aedd5975137cfa9bf7d7329a2d6413f6d6e364b252f4386222957eed":"Swap"},"profit":"0
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,{"LINK/WETH":{"0x95eea1cedccffc405d0cb9743360712b69a295a66fe0649b5ab1b067869f05fa":"PreAttack","0xf259718ee2f81b543bbfbe2f236cd4235651f8365ec8944741a3c7f3242f06b9":"Convert","0x525929006fc3f089d67b6596f53c5ebe6b82de1f8d3cdeb397f1f55ff4937c47":"Swap"},"profit":"0
后续攻击者又尝试攻击Sushiswap的其他相关仿盘项目，如LuaSwap：
https://etherscan
function_toETH(addresstoken){..
New：0x280ac711bb99dE7C73FB70fb6DE29846D5e4207Ffunctionconvert(addresstoken0,addresstoken1)public{//Atleastwetrytomakefront-runninghardertodo
function_toETH(addresstoken,uintamountIn){...}
可以看到区别在于：代码第26行_toWETH限制了amount，这样修改以后就不会将SushiMaker中存的全部SLP都去池中换成wETH，而只是换取burn出的一部分
但是这样问题就解决了吗？其实还没有，时隔两个月，同样的地方，Sushiswap又中了见：amenda：SushiSwap攻击事件(2021年1月27号)分析(https://zhuanlan.zhihu.com/p/372058217)
0x3.参考
以小博大，简述SushiSwap攻击事件始末：https://www.chainnews.com/zh-hant/articles/726256718885.htm
Astokenpricerisesandreputationmends,Sushiswapfoilsmidnightexploit:https://cointelegraph.com/news/as-token-price-rises-and-reputation-mends-sushiswap-foils-midnight-exploit
AnevolutionofUniswapwithSUSHItokenomics：https://sushichef.medium.com/the-sushiswap-project-dd6eb80c6ba2
一文看懂Uniswap和Sushiswap：https://zhuanlan.zhihu.com/p/226085593
sokdecentralizedexchanges(dex)withautomatedmarketmaker(amm)protocols:https://arxiv.org/abs/2103.12732
AttackingtheDeFiEcosystemwithFlashLoansforFunandProfit:https://arxiv.org/abs/2003.03810
https://www.blocksecteam.com/
contact@blocksecteam.com
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